A man standing on a crowded Muni train pulls out a .45-caliber pistol.
He raises the gun, pointing it across the aisle, before tucking it back against his side. He draws it out several more times, once using the hand holding the gun to wipe his nose. Dozens of passengers stand and sit just feet away - but none reacts.
Their eyes, focused on smartphones and tablets, don't lift until the gunman fires a bullet into the back of a San Francisco State student getting off the train.
Rick Perlstein on Survivalism from the 1960s to Now
Ezra Klein talks with Janet Rosenbaum, an assistant professor of epidemiology at the School of Public Health at the State University of New York (SUNY) Downstate Medical Center School
by Rick Perlstein
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